let http = require('http')

http.createServer(function(req,res){
    res.writeHead(200,"ContentType:texr/html")
    res.write("<head><meta charset='utf-8'/><head>")
    res.end("<h1>hello world</h1>")
}).listen(8081,'127.0.0.1',function(){
    console.log('nodejs 成功启动')
})